1. Field of the Invention
The present invention relates to a passive seat belt device for use in a motor vehicle, which has a shoulder belt automatically brought into its tightening and releasing positions in response to the opening and closing operations of a door of a motor vehicle.
2. Description of the Prior Art
In a seat belt device, having a shoulder belt, for use in a motor vehicle, one end of the shoulder belt is fixed to the inner wall of a compartment at the position behind the shoulder of an occupant in order to tightly hold the breast portion of the occupant. This shoulder belt, however, tends to contact with the neck portion of an occupant in its tightening position to thereby bring about an uncomfortable feeling for the occupant.
In a manual seat belt it is known to fix a small hook to the side portion of the head rest of a seat cushion, with which a shoulder belt is engaged. The small hook keeps the shoulder belt away from the neck portion of an occupant by positioning the one end portion of the shoulder belt downward of the fixing end of the same.
However, such a small hook cannot be applied to a passive seat belt since it does not allow the shoulder belt to move upward and downward therein and thus does not hold the same. Further, in a passive seat belt device, the shoulder belt sometimes contacts with the neck portion of an occupant when the seat belt is automatically moved away from the occupant at a high speed in response to the opening operation of the door.